This invention relates to magnetic separators and, more particularly, to magnetic separation of magnetic material in refuse.
With more and more emphasis being placed on recycling, it is becoming more desirable to recover salvageable articles from otherwise discarded material. Much of the metalic material discarded as refuse can generally be recycled for one purpose or another, provided it can be efficiently separated from the remainder of the refuse. The metalic material intended to be recaptured is generally also magnetic so that magnetic separation is a possibility for recapture. However, the nonmetalic material, e.g., paper, is usually light and tangled with the magnetic material and thus subject to being carried along with the magnetic material, making complete separation difficult, if not impossible. Also, in some cases it may be desirable to separate the lighter material (e.g. paper) for recycling.
There are various designs of magnetic separators, none of which, to the inventor's knowledge, insure complete separation of magnetic material from nonmagnetic material.
One type of magnetic separator provides a continuous belt moving through a magnetic field generated by a magnetic assembly, the magnetic assembly being positioned above a portion of the belt. The magnetic assembly typically comprises a plurality of magnets magnetically coupled together. Magnetic objects are attracted to and carried along the belt, while nonmagnetic objects fall away from the belt and are thereby separated from the magnetic objects. A problem with this type of magnetic separator is that heavy magnetic objects sometimes fall away from the belt as they are transferred from one magnet of the magnetic assembly to another, and are irretrievably lost.
Barrett, et al., U.S. Pat. Nos. 3,890,239 and 3,935,947, both entitled "Magnetic Refuse Separator," disclose magnetic separators.